Using trees instead of telescopes to find the stars: this week on The Dark Sky

Jul 4, 2016

The star-spangled oak at Headlands International Dark Sky Park Edit | Remove

Summer is upon us and the Moon will be a beautiful crescent moving up the sky from the western horizon this week. But did you know that today July 4 the Earth is as far away from the Sun as it can get on its orbital path?

All of the planets, including Earth, move around the sun in elliptical pattern. Curiously, the Sun does not occupy the center of these ellipses, but one of the two focal point with in the ellipse.

This geometric harmony was first described by 16th century German astronomer Johannes Kepler, who made beautiful use of the Platonic solids to calculate the orbital rhythms of the planets, and to determine things like when they orbit closest and furthest away from the Sun.

But doesn't it seem strange but here we are, at the beginning of our warmest season in the northern hemisphere and we are actually furthest away from the Sun right now?

I love these kinds of cosmic contradictions, like using a forest of trees instead of a telescope to find the stars. Wait, what?

An hour after sunset, when the first stars start to appear, the trees can be a magnificent aid to night sky viewing. If you are just learning the constellations, a break in the treetops allows for focusing on isolated regions of the sky without getting lost in a wide open Vista. If you are a seasoned stargazer, the trees offer the friendly challenge guessing which stars they hold a loft in the night.

The English romantic poet John Keats described just such a scene in his epic poem "Hyperion" when he wrote the words: "... As when, upon a tranced summer night, those green rob'd senators of mighty woods, tall oaks, branch-charmed by the earnest stars, dream, and so dream all night..."

After all the fireworks of the season, as the Earth rolls away from the Sun and the Moon sweeps up West over the horizon, may you find your way out under mighty trees, branch-charmed by the stars.